Questions tagged [snubber]
A snubber is a circuit used to suppress transient voltages in electrical circuits. It can include RC snubbers that comprise a resistor and a capacitor in series, often used for AC circuits, and also a diode used across relays and other inductive components to suppress their inductive 'kickback'.
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RC snubber causing latch in relay
I'm driving RT314730 relay directly with MOC3063:
simulate this circuit – Schematic created using CircuitLab
The problem is when SW1 is open the relay latches, I tried 10nF instead of 100nF and ...
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Is this circuit sufficient?
Firstly I am sorry for this bad drawing but I just got it from the internet.
Secondly I'll give a brief idea about the project it is a static switch would be used to drive general loads (inductive and ...
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Snubber circuit protection
I am trying to understand how to implement snubber circuit protection as I have seen different circuit diagrams, I am lost.
Image source: Homemade Circuit Projects - Prevent Relay Arcing using RC ...
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Two switch flyback converter MOSFETs voltage stress
I am exploring and experimenting the two switch flyback converter. I have a doubt, in this two switch flyback converter configuration, two MOSFETs are connected in series with sandwiched primary coil ...
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Relay + RC Snubber to switch contactor - parasitic voltage?
I have designed yet another custom PCB with an ESP32 and some relays that I will use for some IoT projects.
I am using one of these relays to switch a 230 V AC contactor which then switches a 230V AC ...
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MOC3041 typical SSR circuit, when snubber is applied, triac never turns off
I am trying to make this circuit:
I got reference from this site, which is very useful, thanking them for info;
https://components101.com/ics/moc3041-zero-cross-triac-driven-optoisolator
Despite all ...
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LTspice snubber simulation
I'm attempting to simulate a bi-directional snubber to limit the peak voltage when switching off, as shown in the picture below. The resistance of R2 changes from 1 mΩ to 1 MΩ when a current of 1 kA ...
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Driving 2-way synchronous motor valve with SSR
I need to control a 2-way 3-wire 230VAC synchronous motor (6W) driven HVAC valve with SSR. (This is a custom thermostat with heating-cooling valve controller).
The valve internal circuitry is ...
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Is this RC Snubber functional?
I had made this circuit which is basically works somehow as a UPS (when there is a power failure from the mains (220 VAC) the inverter line turns on and keeps the load on) and yes I had tested the ...
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Do I need a snubber in a snubberless triac?
I am trying to make this circuit and using the Triac as a switch. I am using in this one a BTA06, although I will upgrade it to a BTA12 so it can handle 220 V 1000 W easily. It will be implemented in ...
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Is it superfluous to place a snubber in parallel with a diode by default?
I'm a VHDL guy for work, and play with power converters on the weekends so please forgive if this question is dumb.
When using MOSFETs, IGBTs, or SCRs in power converters, it is typical to see ...
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RC Snubber Design Hint for 3 phase AC-AC PWM Chopper
Im trying to design a 3 phase Ac-Ac Pwm Chopper, I'm having difficulty designing the snubber network for the mentioned topology.
Now I tried testing this circuit on bench , with my IGBT snubber values ...
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How to put a decent snubber to the MOSFET?
I am trying to make a soft starter for an inverter to make the turn on process as a yield curve like the one in the photo:
so I used this circuit :
however, the problem is still visible in the turning ...
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Driving a 12V DC small pump with a MOSFET
I need to drive a small immersion pump with a 5V output of a microcontroller. I found easy to find this mosfet: https://www.sparkfun.com/datasheets/Components/General/RFP30N06LE.pdf
By looking at the ...
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How is an RCD snubber different from an RC low pass filter?
The RCD snubber is used in flyback SMPS designs where AC-DC conversion is carried out. I know that a snubber circuit is used; its purpose is to filter transients. According to my understanding, the ...
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Should a flywheel diode be installed for SSR with AC load and DC input?
I have a solid state telay (SSR) that switches a 240 V AC appliances's input based on a 24 V DC input. The relay takes 24 V DC input and controls a 240 V AC connection.
I understand that for DC loads, ...
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24 VAC TRIAC snubber circuit
I need to set up a circuit to drive a valve with an inductance value of 0.16 H and 24 VAC, 50 Hz, and I found the circuit in the picture by researching.
If I build a snubber circuit for the TRIAC, ...
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How to mitigate excessive ringing in VDS and VGS
I have a few questions regarding my measurement results in the lab for a double pulse test setup. There are three issues which I want to mitigate
.
At turn-on interval, there is excessive ringing in ...
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RC snubber network not protecting IGBT
I'm working on an electromagnetic accelerator project but I'm having trouble protecting my IGBTs that switch current through the coils. Here's the schematic:
C1 gets charged to around 250 V (In my ...
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Interference from compressor pressure switch
In my CNC machine, I have a small air compressor and a spindle motor VFD connected in same 240 VAC outlet.
Whenever the compressor switches on or off, the VFD reports "OC-o" error. According ...
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Snubbing an H-bridged motor
Mostly a follow up to https://electronics.stackexchange.com/questions/175778/rc-snubber-across-switch-or-inductor…
I've seen RC or RCD snubbers across the switching MOSFETs (and these damp the dV/dt ...
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Designing a simple controller for a hot plate
I have a hotplate with a TS port meant for an external temperature control unit. The manufacturer's customer service told me that this port is not connected to anything internally in the model I own. ...
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PWM driven 24 V fan noise issue
I have a weird issue with a 24 V blower fan. We are driving it with an N-channel MOSFET at a PWM freq of 12 kHz. It has a periodic artifact that appears about 230 Hz or so.
Observable behavior ...
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RC snubber not working when R > 0
I am running a 40 Ohm heating element directly connected to a 180 Volt, 8 A (@ max power) PV array. I am trying to use an RC snubber to protect the switch. I calculated the R and C values using this ...
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What is a "snubberless" TRIAC? How does it compare to a standard device?
I was searching for a TRIAC to be used as part of a pre-charge circuit for large DC link capacitors, and found one (T435T-600FP) that is described as "snubberless". An on-line search did not ...
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Sizing a RC Snubber - microcontroller restarting when switching off an inductive load
I'm trying to drive an 220 V solenoid water valve with a relay, but I'm having problems: when I turn off the solenoid, the microcontroller reboots.
I believe the source of the problem is the spike ...
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What is the function of varistor in this design [closed]
Came across this on internet. The description mentioned this module help prevent relay stick to the contact. Please explain why varistor need to be included in the design if it is to connect in ...
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Inverter MOSFET Snubber: RC or Schottky diode?
I've researched this question and found a lot of theory, but not much practical anecdotal experience. I would like to hear from those with physical knowledge of this.
I've constructed a transformer ...
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RLD + RC Snubber for MOSFET
I'm currently making a DC-DC SMPS power supply that converts 331VDC (rectified from 240VAC) to 60VDC with a maximum output current of 10 amps. I've asked once on this forum about a general problem on ...
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Snubber circuit for electromagnet
I have run into the same problem described here and here, when I added diode to electromagnet. Basically, the magnet still holds with about 20kg force several minutes after removing power. The ...
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What causes spikes on a primary push-pull transformer with good snubber and tvs?
I am repairing 8 second-hand microgrid inverters from 2013.
The internal structure is a push-pull sinusoidal current generator. DC input 12 to 28V, 250W. The primary side suffers from a design problem....
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Noise suppression circuits for a 120VAC motor
I am building a circuit for a relay that controls power to a 1000 watt pump motor. I want to do what I can to reduce noise and failure of the circuits from transients etc.
Here is my schematic:
I ...
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Decoding SPICE Model for onsemi SZ1SMB5939BT3G 30V Zener
I would like to model using the onsemi 1SMB5936BT3G (30V Zener Diode) SPICE model, but the SPICE model is not acting as I am expecting. Built-in LTspice Zeners clamp the kickback no problem but the ...
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Distorted output waveform and snubber heating in 3level 3 phase inverter
We are working on 3-level 3-phase 400Hz inverter (110Vrms).
The problem is that the output wave still have some harmonics of the switching frequency.
The snubbers are heating up rapidly when connected ...
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AC element control using TRIAC and optocoupler
I recently came across this circuit and I'm trying to understand it. This is designed to control an AC heater using a T435-600B-TR TRIAC and an MOC3063S optocoupler, connected to an Arduino Uno.
From ...
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Arc suppression on electromagnet circuit
I have an application where an aluminum arm is contacting a steel spring and there is a lot of arcing. The contact energizes a 12v electromagnet with a 47ohm coil drawing 250mA and a 4700uF cap to ...
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Can I use a single snubber circuit for multiple triacs?
I am building a triac sprinkler controller using BT136S-800,118 triacs with a microcontroller for control. The triac driver (MOC3021M) suggests a snubber circuit for an inductive load.
I have two ...
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Snubber Filter Circuit Not Working Triac Dimmer
Hi I am working on a project using a triac to do phase control dimming of 120V ac powered devices. I recently translated my project from perfboard to SMT using an SMT fabrication service. The project ...
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Trace clearance and creepage distance between similar high AC voltage paths
In my project I need to control 2 relays from ESP-12E,
I have isolated AC & DC side in my PCB design by 4mm
PCB Material : FR4, with general Silkscreen coating (green polymer coated)
According to ...
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Unwanted motor influence (RC snubber?)
Trying to make motors control, but have very significant influence of the motors between each other.
When first motor is stopped (by built in limiter) second one (stopped) start turning cca 1/4 of ...
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Understanding flyback power supply with weird snubber circuit, and general function?
Hello fellow wanderers of the electromagnetic plains,
I'm looking to replicate the function of the below pictured reference design, just a simple 230VAC SMPS using an iW1700 chip (72kHz operation), ...
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Transformer energy snubber
I own an older PC speaker set with a 10 V AC power supply.
The power-cube transformer not only has a sine with flatted tops, but also, when I turn off the speaker set, my sleeping PC wakes up. I guess ...
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Triac driving motor with limit switch, needs protection?
I'm trying to drive a bunch of motorized ball valves from an ESP32.
These valves have a 230V AC motor with one common wire, and two wires to set direction (open/close). When powered between common and ...
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TRIAC motor control. Why is my resistor burning?
I have designed a digital motor controller using the following circuit. One of my resistors keeps overheating.
There is a zero-cross detector elsewhere in the circuit used to time the firing of the ...
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relays 5V 10A and 12V 30V stop working after a few days of use
We built a system for heating 3 bioelectrochemical reactors, but after a certain time of operation the system starts to heat up. We identified that when this occurs, the relay works despite the light ...
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RCD clamp and RC snubber design question
I have two questions about the RCD clamp and the RC snubber question in flyback.
Below the figure is a CCM flyback converter with primary and secondary clamps and snubbers.
Here are my questions:
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Snubber in low power Push-Pull DC/DC converter
I'm designing a low-voltage and low-power push-pull converter for an isolated communication interface. The output will be 5 V, 0.5 A. I would like to have an hint about snubber networks on the primary ...
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Sub-miniature signal relay (normally closed SPDT) getting stuck due to arcing
I have a 24V motor which is driven bi-directionally with PWM using DRV8873 H-Bridge motor controller.
The circuit looks as follows:
For normally driving the motor in either of the direction, I switch ...
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Why a low pass filter across relay contacts instead of a high pass filter?
I have found a snubber, it is a low pass filter. It doesn't make sense to have a low pass filter across the contact. I would consider transients such as arcing to be high frequency; therefore, a high ...
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Switching motor through contactor using 5V mcu signal
Is the following procedure safe/ok?
MCU turns on the optocoupler (MOC3063, datasheet)
Optocoupler output turns on a triac (BT139-600, rated 16A, 600V AC)
Triac supplies 220V AC voltage to the bobbin ...
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